Vasily Maximov/AFP/Getty

KIEV, Ukraine—He took the Black Sea peninsula of Crimea with just a few shots fired. The Donbass region is a harder nut to crack—the Ukrainians are determined to keep it. And so we wait for Russian President Vladimir Vladimirovich Putin to see what he wants to do with the tanks and armor and the uniformed men without insignias that have crossed this week from Russia into eastern Ukraine in large numbers—the ones he insists he never sent who are purely a figment of NATO’s malevolent imagination.

This weekend Putin takes his seat alongside world leaders at the G20 meeting in Brisbane, but that is no guarantee of Russian restraint in the days ahead. The lying game is second nature to him now. Whatever happens, he won’t admit, acknowledge, or accept the implication of responsibility.

The brazen land grab of Crimea was planned while Putin was enjoying the limelight of the Sochi Winter Olympics. His poker face, punctuated with occasional stiff smiles will give no clues in Australia about what he is planning to do with the scores of armored vehicles and accompanying infantry that have been snaking along Ukrainian roads, according to a monitoring mission of the Organization for Security and Co-operation in Europe.

The September ceasefire, struck after Ukrainian security forces and volunteer battalions grabbed back a string of towns in Donbass, served only to reduce the intensity of the conflict, not to end it. The truce-that-wasn’t has been violated daily by men who came from Russia.

Now the clashes have increased again almost to the level predating the September 5 ceasefire. Thursday night was busy with pro-Russian separatists and the so-called “little green men” testing and provoking with Grad rocket shelling of the ruined Donetsk airport and of various strategic Ukrainian checkpoints from Luhansk in the north of the region to Horlivka to the east of Donetsk.

“Terrorists [meaning Russians and their supporters] have violated the terms of the ceasefire 50 times in the past 24 hours” and “six Ukrainian soldiers have been wounded in fighting over the past day,” the press office of Ukraine’s Anti-Terrorist Operations Center said on Friday morning. “There was another attempt to storm the [Donetsk] airport last night. The attack by bandits was repulsed, and this strategic facility remains under our control.”

Ukraine’s security spokesman Andriy Lysenko insists pro-Russian separatists started the fighting, saying, “the Ukrainian military responded to artillery and mortar attacks.” He said Friday morning one Ukrainian soldier had been killed.

To try to counter the Russian military build-up, Kiev has redeployed more forces eastward. Commanders of increasingly nationalistic volunteer battalions have warned Ukrainian President Petro Poroshenko that he has to respond to Russian provocation or face the consequences. One commander has threatened a military coup if Kiev concedes anything to the separatists.

Is the Russian military buildup, as some analysts argue, just Putin’s way of negotiating with the West, using escalation to strong-arm concessions and maybe even to coerce a reduction in the U.S.-led economic sanctions on Russia?

In the run-up to the Brisbane meeting the Russian President noticeably focused his public comments on the sanctions that were ramped up after the Crimea grab and the Moscow-encouraged separatist agitation in the Donbass oblasts of Donetsk and Luhansk.

“The sanctions run counter to the very principles of G20 activities and to international law, as they can only be introduced via the United Nations,” Putin told the Russian news agency TASS.

He stressed also the effects sanctions have on Europe, saying, “everyone must understand that the global economy and finance these days are exceptionally dependent on each other” and arguing there’s blowback. “Our cooperation with Germany gives that country some 300,000 jobs. If there are no contracts, these jobs may be lost.”

NATO officials aren’t specifying how much Russian equipment has come across the border in recent days. But one convoy alone, according to Lysenko, consisted of 32 tanks, 16 D-30 howitzers and 30 KamAZ heavy trucks. Ominously, NATO officials say air-defense systems have been sent across and high-grade jamming equipment that is disrupting the drone flights the OSCE uses to monitor the border.

For Ukraine’s leaders this all smacks of prelude to a full-scale invasion. On Thursday, Ministry of Internal Affairs adviser Zorian Shkiriak spoke to reporters of “the likelihood of another invasion of Ukrainian territory by the regular army of the Russian Federation.” He added: “We must we ready for it.” A full-fledged attack can occur at anytime, he argued.

But attack where? In Ukraine’s capital Kiev there is an atmosphere of dread: for months now people have been riding an emotional roller coaster when it comes to the east. Intense fighting has provoked the fear that Donbass isn’t where Russian tanks will stop. And with each turn of the destabilizing screw, muscular Russian language and panic among Ukrainian officials has added to the alarm. In late August, state-run TASS reported Putin told a youth forum, “I want to remind you that Russia is one of the most powerful nuclear nations. This is a reality, not just words.”

The bullying this time round may be no more than that—a provocation to make Kiev think twice about ever thinking about getting the Donbass back, except, perhaps, as a semi-autonomous part of the country where Moscow indirectly calls the shots. Or it may be the start of an offensive led by separatist proxies to re-take significant towns lost in the summer like Kramatorsk and Slovyansk and to move against Ukrainian forces in the coastal city of Mariupol, which has remained in Ukrainian hands throughout the months-long agitation.

Shelling and hostilities around the Donbass region’s second largest city on the Sea of Azov have continued throughout the week, reviving fears that Mariupol, whose local population has never thrilled to separatist ideas, is the target of this new buildup to carve out out a land-link from Russia to Crimea.

If it is, then it would be a significant change in the pattern of the low-intensity conflict so far, requiring not a takeover from within, which was how Donetsk and Luhansk fell into separatist hands, but a storming from without.

If Putin’s fellow summiteers in Brisbane ask him what he intends, he might even bless them with a rare smile, and perhaps ask for their help to calm a situation over which he, of course, has no control.